One such tool is known from DE 32 32 804 C2. For the clamping fixing of the cutting blade there is provided a clamping wedge which is actuated for the clamping of the cutting blade carrier by means of a differential screw (double-threaded bolt). An adjusting screw with a wedge-shaped front-end member is provided in order to be able to pivot the cutting blade carrier, with the result that a radial adjustment of the cutting blade is effected. This fine adjustment of the cutting blade is comparatively time-consuming, because in order to correct an over-adjustment of the adjusting screw it is necessary to release the mechanism and to carry out the screw adjustment anew. This has to be repeated until the desired cutting diameter of the tool has been set.
From EP 0 544 658 B1 there is known a further tool of this type, in which a cutting rib is arranged on a rib-like carrier (cassette). This carrier or cassette has semi-cylindrical recesses which together form cylindrical pockets for a boring rod. In order to adjust and clamp the cassette, two adjusting screws are provided, while for the axial adjustment of the cassette an adjusting screw is provided which presses against the cassette by means of a ball. A securement of the cassette is effected by means of the adjusting screws. Here again there is the problem that the adjustment of the cutting diameter requires the expenditure of time because of repeated releasing procedures. Further, because of the mounting of the cassette on the associated longitudinal wall, a narrowing adjustment of the cutter to guarantee the cutting function is not possible.
FR 2615769A describes an adjustment device for a cutting tool in which a rounded cassette received in a bore carries the cutting blade and is adjustable by means of a screw having two threads of different characteristics. In order to make possible a transverse displacement of the cassette, a groove/rib engagement with the screw is provided. A narrowing adjustment of the cutting blade is not possible with this construction.
In a tool holder for tools for chip-producing working according to DE 30 07 322A the cutting tool comprises a cutting blade which is exchangeably clampingly fixed by a clamping member and which is adjustable as to its radial position by an adjusting member by way of a cutting blade carrier serving as adjusting means. In order to adjust the cutting diameter repeated releasing procedures are necessary. A further adjusting member for the axial adjustment of the cutting blade carrier has its head in automatic shape-fitting engagement in a complementary recess thereof such that the cutting blade carrier can be retracted or alternatively advanced in the axial direction by the latter adjusting member.
From CH-PS 449 390 there is known a reamer with coolant supply, whose tool body is provided with a central longitudinal bore leading to the cutting head, from which longitudinal bore a plurality of cross-bores extend outwardly at an angle between the blades. By means of these bores, coolant and lubricant are supplied in order to cool and lubricate the cutting head during the cutting process.
In a reamer with adjustable cutting head described in DE 32 34 238 A, a central coolant bore is provided which branches into two diverging branch bores which extend forwards at a shallow angle to the shaft of the conical screw.
According to EP 0 215 144 B there is provided a reamer with cutting head expandable by a conical screw, with the cutting head having a coolant channel extending axially through the reamer shaft, the coolant channel running into a threaded bore receiving the threaded shaft of the conical screw and subsequently to this communicating with a hollow cylindrical portion of the reamer shaft expandable by the conical screw. Between the hollow cylindrical shaft portion and the conical screw there is an annular channel which is connected to the axial coolant channel by means of an axially parallel coolant channel in the conical screw. From the annular channel there extends at least one channel between the cutters, with this channel being directed forwards at an angle between 30.degree. and
Automatic reamers are also known in which the coolant is guided through the shaft directly to the cutters.